target/linux/at91/patches-5.10/135-net-macb-Correct-usage-of-MACB_CAPS_CLK_HW_CHG-flag.patch

   1 From 982347f757b85ef526afaf243867ddd515475e1b Mon Sep 17 00:00:00 2001
   2 From: Charles Keepax <ckeepax@opensource.cirrus.com>
   3 Date: Mon, 4 Jan 2021 10:38:02 +0000
   4 Subject: [PATCH 135/247] net: macb: Correct usage of MACB_CAPS_CLK_HW_CHG flag
   5
   6 A new flag MACB_CAPS_CLK_HW_CHG was added and all callers of
   7 macb_set_tx_clk were gated on the presence of this flag.
   8
   9 -   if (!clk)
  10 + if (!bp->tx_clk || !(bp->caps & MACB_CAPS_CLK_HW_CHG))
  11
  12 However the flag was not added to anything other than the new
  13 sama7g5_gem, turning that function call into a no op for all other
  14 systems. This breaks the networking on Zynq.
  15
  16 The commit message adding this states: a new capability so that
  17 macb_set_tx_clock() to not be called for IPs having this
  18 capability
  19
  20 This strongly implies that present of the flag was intended to skip
  21 the function not absence of the flag. Update the if statement to
  22 this effect, which repairs the existing users.
  23
  24 Fixes: daafa1d33cc9 ("net: macb: add capability to not set the clock rate")
  25 Suggested-by: Andrew Lunn <andrew@lunn.ch>
  26 Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
  27 Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com>
  28 Reviewed-by: Andrew Lunn <andrew@lunn.ch>
  29 Link: https://lore.kernel.org/r/20210104103802.13091-1-ckeepax@opensource.cirrus.com
  30 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
  31 ---
  32  drivers/net/ethernet/cadence/macb_main.c | 2 +-
  33  1 file changed, 1 insertion(+), 1 deletion(-)
  34
  35 --- a/drivers/net/ethernet/cadence/macb_main.c
  36 +++ b/drivers/net/ethernet/cadence/macb_main.c
  37 @@ -464,7 +464,7 @@ static void macb_set_tx_clk(struct macb
  38  {
  39         long ferr, rate, rate_rounded;
  40
  41 -       if (!bp->tx_clk || !(bp->caps & MACB_CAPS_CLK_HW_CHG))
  42 +       if (!bp->tx_clk || (bp->caps & MACB_CAPS_CLK_HW_CHG))
  43                 return;
  44
  45         switch (speed) {